My experience with silent migraines is that I pass through the other three phases of migraine, but my body skips the pain step.
My symptoms started two years ago. I started with shoulder pain, which progressed toy entire arm feeling pins and needles. The pins and needles moved (over time) to all limbs and my face. They have improved now, but still come on occasion. Other symptoms include dizziness, feeling like I can't keep my eyes open, lack of balance, Total exhaustion, dropping things, brain fog, and nausea.
I am thankful to be learning things that help. I take CoQ10 and magnesium supplements. I also made major changes to my diet, exercise, drink tons of water, drink less caffeine and get lots more sleep than I used to. Another huge help has been a very recent addition: tinted glasses. I put them on when I'm feeling a flareup coming on, and they help a lot. I just got started with an upper cervical chiropractor as well and feel very hopeful about that.
I truly appreciate this group. I'm learning so much from all of you. Thank you for helping feel like others understand!

I sometimes have silent migraines, and have never had it show up on an MRI

"Migraines" cannot be "seen" w any imaging protocols. Plaques, brain abnormalities, vessel abnormalities, etc are the only thing that can be imaged.

Thank you so much, everyone. I truly appreciate your responses.

I too have 'silent migraines'. Took me a couple of years to figure it out. I present with maybe a mild all over headache then progress thru the other migraine symptoms - visual disturbances, nausea/vomiting, light/sound sensitivity, vertigo. Occ with abdominal pain and blood pressure problems. I would have thought Not having that hammer in my head would make migraines easier to deal with but it doesn't. Partly, I think I miss some of the more subtle initial symptoms so by the time I realize I'm having a migraine - I'm full blown and down for the count. I've started on low dose amitriptyline and it's helped tremendously. But I still must be vigilant to my specific prodrome symptoms.
I've read about ct's showing small clusters at specific points in the brain. Tiny milky areas that may or may not be related to migraines. I think - this is my opinion now - that if a brain is misfiring, repeatedly in an area, then the brain may try to protect itself. It's like there's a small fire in there and the body is trying to contain it. So far, studies are slim and so docs make the migraine diagnosis by ruling out everything else.
I wish you and the rest of us well on our migraine journey.